Whenever we have seminars or events on performance tuning of MySQL we always get a good crowd. We've got two performance tuning seminars in the afternoons next week in DC and Boston on Tuesday and Wednesday. There are also morning sessions targeted to managers who want to reduce risk and costs. These are free events and are targeted primarily to OEM / ISV users who embed or bundle MySQL. Still, they are a good way to get some tunings tips and meet others. We'll also figure out a way to get this content online for folks outside of these cities.... READ MORE
Tomorrow, Thursday 13th Sept. at 13:00 UTC (15:00 CEST/9:00am EST/6:00am PST) Jan will perform a MySQL University session providing an Overview of the MySQL Proxy. If you like to attend, please add your name to the session page and read the Instructions for Attendees. All you need is a PDF viewer to see the slides, an IRC client to post questions and comments and an application capable of playing an OGG audio stream.
Version 0.6.0 of the proxy has just been tagged and we're waiting for the mirror sites to catch up before we publicly announce …
[Read more]Monty Taylor posted interesting investigation of the fact read_buffer_size variable affects connection speed.
This is not something you would expect right ? me too. Not only global user data is expected to be cached on startup but even if it is not why would you do full table scan to fetch single user information ? Something is fishy here and perhaps bug needs to be filed either resulting in fixes or docummentation updates.
The great thing you see from this post is - o_profile (often together with strace) are great tools for MySQL Performance analyses. Too many people end tuning on plans and indexes while there well could be some internal gotchas.
The next Monty comes up with 2 posts on …
[Read more]Using the instructions followed in JRuby Hack Day and taking some help from Nick, I figured out how to use the JDBC connection pools configured in GlassFish using the JNDI names.
All the commands given below are relevant for GlassFish but the same concept will work where ever you deploy your WARed up JRuby on Rails application.
- Follow the bullet #1 and #2 from …
my girlfriend's grandfather wants a blog!
During the MySQL User’s Conference in Japan, we’re offering people the opportunity to test their knowledge with a practice exam. The exams are going to be available in Japanese as of Sept. 25.
Today, we upped the ante a bit when Pearson VUE were so kind as to bring along some very nice prizes to hand over to those that answered all questions right.
Attaining those prizes turned out to be a lot harder than we expected… it took several hours before we finally got a winner and I got to hand over a nice notebook to none other than Kei Sakai from the MySQL Nippon Association.
Thanks again to Pearson VUE for not only being here at the conference …
[Read more]I am of the attitude, the day you stop learning something is the day you die. I’m not prepared to induce MySQL into both sides of that equation, however some days it never ceases to amaze me what little thing I didn’t know about MySQL.
Today I saw in reviewing SQL statements for an application SELECT LAST_INSERT_ID(). No big deal, that is expected, however I then saw UPDATE … SET id=LAST_INSERT_ID(id+1) WHERE …
Having never seen this syntax I was forced to review it’s usage. See MySQL Documentation
If expr is given as an argument to LAST_INSERT_ID(), the value of
the argument is returned by the function and is remembered as the
next value to be returned by LAST_INSERT_ID(). This can be used
to simulate sequences:
1.Create a table to hold the sequence counter and …
[Read more]VMWare open sources Tools product. Sun adds virtualization features and PostgreSQL to Solaris 10. MySQL releases MySQL Enterprise update. (and more)
VMware Unveils VMware Tools as Open Source Software, VMWare (Press Release)
Sun’s Solaris 10 Advances Virtualization and Network Performance, Incorporates Open Source PostgreSQL Database, Sun Microsystems (Press Release)
MySQL Enterprise Simplifies Database Scale-Out with New Automated Replication Monitoring & Advisory Tools, MySQL AB (Press Release)
Embedded Systems Developers Demand Access to RTOS Source …
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I had a machine with 4 nics that I wanted to bond 2 by to. I had no problem getting the bond0 device up witn any of the interfaces, however getting a bond1 up always resulted in the above error.
The friendly guys from #centos on freenode pointed me to the missing config.
options bonding mode=4 max_bonds=4
An important thing to keep in mind here is that in the RHEL/CentOS initscripts package, these options are global. There is no way to set a different set of options for each bond. So, if for instance, you had 4 NICs and wanted to have 2 of them bonded in mode 1 and 2 of them in mode 4, you’re SOL. (Unless, of course, you go for insmodding everything by hand. But that’s ugly)
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